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Wouldn’t it be nice to be able to know why your boat has a tendency to porpoise? And nice to know how you can improve or eliminate a porpoising problem? The causes of porpoising and how to correct it are frequently mystifying accounts. Here is an explanation of porpoising, how to design to mitigate the potential for porpoising and how to fix it when it’s a problem.What is Porpoising?
Porpoising is the cyclic oscillation of a boat in pitch and heave, of sustained or increasing amplitude, occurring while planing on
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I receive many questions about the cause and effects of "blowout". Here is an explanation of blowout and causes and cures.

Most all high-performance boaters have experienced the circumstance that restricts their maximum velocity to less than it could be, even though they’ve got the horsepower available to use. This phenomenon is commonly called "gearcase blowout” or "propeller blowout".

Blowout occurs when something causes air/water mixture in the region of the propeller to become sufficiently disturbed that the
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The Vee-bottom hull is the most common design in modern performance powerboats. The Vee design has a number of variations and near-endless modifications – including the pad-vee design - that can enhance particular handling characteristics of the boat. If going fast is the objective, it’s worthwhile knowing just how a vee pad can affect vee hull performance.

I’ve had many inquiries about vee hull modification, vee-pad hulls and pad modifications. High performance vee pad hulls must be carefully designed for each boat, as the balance of lift from the pad is crucial. The good news is that there are ways that we can engineer our way to the best performing
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Chine walking can arise with any high performance vee-hull. Chine walk is an aggressive, often rapid, side-to-side oscillation of the hull. Acute cases of chine walking grow more severe by themselves – called a “self-excited oscillatory instability”. Really severe cases can see the boat bouncing from one chine to the other chine – and some hulls can chine walk in the middle of a turn! It can be a scary ride for even the experienced pilot. So let’s explore the facts of “chine walking” – why it happens
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